This mineral was first noted in 1937 but was not described in detail until 1971. It has not yet been seen as a gem, but the high hardness would allow it be worn with no risk of scratching. Holtite is now considered to be a variety of dumortierite. The mineral comes from the one locality, and a cut stone would have to be considered a great rarity.
Optics:a= 1.743-1.746; β= 1.756-1.759; γ= 1.758-1.761.
Biaxial (-), 2V= 49-55°.
Occurrence: Alluvial tin deposit near Greenoushes, Western Australia, associated with cassiterite.
Comments: This mineral was first noted in 1937 but was not described in detail until 1971. It has not yet been seen as a gem, but the high hardness would allow it be worn with no risk of scratching. Holtite is now considered to be a variety of dumortierite. The mineral comes from the one locality, and a cut stone would have to be considered a great rarity.
Name: After Harold E. Holt, prime minister of Australia from 1966 to 1967.
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Optics:a= 1.743-1.746; β= 1.756-1.759; γ= 1.758-1.761.
Biaxial (-), 2V= 49-55°.
Occurrence: Alluvial tin deposit near Greenoushes, Western Australia, associated with cassiterite.
Comments: This mineral was first noted in 1937 but was not described in detail until 1971. It has not yet been seen as a gem, but the high hardness would allow it be worn with no risk of scratching. Holtite is now considered to be a variety of dumortierite. The mineral comes from the one locality, and a cut stone would have to be considered a great rarity.
Name: After Harold E. Holt, prime minister of Australia from 1966 to 1967.
This mineral was first noted in 1937 but was not described in detail until 1971. It has not yet been seen as a gem, but the high hardness would allow it be worn with no risk of scratching. Holtite is now considered to be a variety of dumortierite. The mineral comes from the one locality, and a cut stone would have to be considered a great rarity.
